Well packers utilized for isolating a zone in a well below the packer from a zone above the packer for performing a well service operation such as acidizing, perforating, formation fracturing or pressure containment are known. Further, it is known to initially run a packer downhole to a selected position and to set the packer using wireline apparatus. After setting, the wireline is removed from the well and a tubing string is run down the well and attached to such packers for performing the well servicing operation. The packer can then be removed from the well by manipulation of the tubing string and pulling of the tubing string and packer. The packer can then be redressed and used again in the same well or at another location.
Flow through the packer must be prevented for a time in order to connect the tubing string and often to perform the service operation. In such situations, the packer is essentially used as a temporary bridge plug. Typically, in prior art devices, in order to seal off flow through the packer, a pump-out plug or flow control device is installed below the packer. A pump-out plug is subsequently removed by applying pressure through the tubing string to release the plug from the packer with the result that the pump-out plug is left behind as debris below the packer when the packer is removed. Other prior art devices utilize a flow control device, such as a blanking plug, installed in an accommodating profile at the bottom of the packer and later removed by wireline to allow flow through the packer. However, during service operations or connection of the tubing string, debris can accumulate in the bore of the packer above the blanking plug impairing its retrievability. Accordingly, it is desirable that the flow control device be located at the top of the packer. In known prior art tools, the flow control device is moved to the top of the packer by wireline after the packer is set and the tubing string is attached which requires an additional trip on wireline through the tubing string.
In one specific currently available retrievable packer, a tubular mandrel is connected to a wireline setting device through a wireline adaptor. A pair of slip assemblies and a sealing unit are mounted on the mandrel of the packer to allow the packer to be set in the well casing and to create a seal in the casing isolating a well zone below the packer from a well zone above it. A slick joint is mounted on the top of the mandrel having a plug receiving annular groove. The adaptor includes an elongated rod which is telescoped through the slick joint and a connecting means frangibly secures the bottom the rod in the joint recess where the slick joint and mandrel are threaded. The top of the rod is connected directly to a wireline setting device. A long sleeve attached to the housing of the wireline setting device rests on the top of the packer. A simultaneous application of force from the housing of the wireline setting device, through the sleeve, to the top of the packer in the downward direction and an upward pulling force on the connecting means provides relative motion between the slip assemblies and sealing unit, and the mandrel required to set the packer. However, since the rod extends through the slick joint past the plug receiving annular groove, it is not possible to seat a flow control device at the top of the mandrel.
A similar type of tool is disclosed in Canadian patent 1,286,602. The adaptor disclosed in that patent utilized for setting the packer includes a rod which is telescoped through the tool and frangibly secured to the bottom of the mandrel. In this tool, as in the previous one, the pump-out plug or flow control device must be located beneath the packer because the rod runs through the plug accommodating profile.